U.S. patent application number 15/503306 was filed with the patent office on 2018-08-02 for closed compressor and refrigeration device.
The applicant listed for this patent is Panasonic Intellectual Property Management Co., Ltd.. Invention is credited to Hiroyuki KAWANO.
Application Number | 20180216609 15/503306 |
Document ID | / |
Family ID | 58099727 |
Filed Date | 2018-08-02 |
United States Patent
Application |
20180216609 |
Kind Code |
A1 |
KAWANO; Hiroyuki |
August 2, 2018 |
CLOSED COMPRESSOR AND REFRIGERATION DEVICE
Abstract
A stator of an outer-rotor type motor is fixed to a stator
fixing member, and the stator fixing member is fixed to a member
(cylinder block) of a compression element, which has a main
bearing. Further, an auxiliary bearing is configured to be separate
from the stator fixing member and is fixed to the stator fixing
member. In this manner, it is possible to fix the stator fixing
member to the member of the compression element in a state in which
an even clearance is formed between an inner circumference of a
rotor and an outer circumference of the stator, and it is possible
to fix the auxiliary bearing to the stator fixing member in a state
in which the auxiliary bearing is reliably coaxial to the main
bearing. Therefore, it is possible to narrow the clearance between
the inner circumference of the rotor and the outer circumference of
the stator such that it is possible to achieve high efficiency of
the motor.
Inventors: |
KAWANO; Hiroyuki; (Shiga,
JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
Panasonic Intellectual Property Management Co., Ltd. |
Osaka-shi, Osaka |
|
JP |
|
|
Family ID: |
58099727 |
Appl. No.: |
15/503306 |
Filed: |
August 4, 2016 |
PCT Filed: |
August 4, 2016 |
PCT NO: |
PCT/JP2016/003598 |
371 Date: |
February 10, 2017 |
Current U.S.
Class: |
1/1 |
Current CPC
Class: |
F25B 1/02 20130101; F04B
39/127 20130101; H02K 21/22 20130101; F04B 35/04 20130101; F04B
39/00 20130101; F04B 39/122 20130101; H02K 11/33 20160101; F04B
39/0044 20130101; F04B 53/22 20130101; H02K 1/187 20130101; F04B
53/16 20130101; H02K 7/083 20130101; F04B 39/023 20130101; F04B
41/02 20130101; H02K 7/14 20130101; H02K 1/2786 20130101; F04B
35/01 20130101 |
International
Class: |
F04B 35/04 20060101
F04B035/04; F04B 35/01 20060101 F04B035/01; H02K 1/18 20060101
H02K001/18; H02K 5/167 20060101 H02K005/167; H02K 7/075 20060101
H02K007/075; H02K 7/14 20060101 H02K007/14; H02K 11/33 20060101
H02K011/33; H02K 21/22 20060101 H02K021/22; F25B 1/02 20060101
F25B001/02 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 25, 2015 |
JP |
2015-165789 |
Claims
1. A closed compressor comprising: a closed vessel that
accommodates an electric element and a compression element which is
driven by the electric element, wherein the compression element
includes a crankshaft that is configured to have a main shaft, an
eccentric shaft, and an auxiliary shaft provided under the main
shaft, a cylinder block having a cylinder bore provided to have a
penetrating circular cylinder shape, a piston that reciprocates in
the cylinder bore, a conrod that connects the piston and the
eccentric shaft, a main bearing that is formed in the cylinder
block and that pivotally supports a load in a radial direction,
which acts on the main shaft of the crankshaft, and an auxiliary
bearing that pivotally supports a load in a radial direction, which
acts on the auxiliary shaft of the crankshaft, wherein the electric
element is an outer-rotor type motor that is configured to have a
rotor fixed to the crankshaft on a main shaft side and a stator
disposed on an inner side of the rotor, wherein the stator is fixed
to a stator fixing member disposed on a auxiliary shaft side,
wherein the stator fixing member is fixed to the compression
element, and wherein the auxiliary bearing is fixed to the stator
fixing member.
2. The closed compressor of claim 1, wherein the stator is fixed to
the stator fixing member through screwing.
3. The closed compressor of claim 1, wherein the auxiliary bearing
is configured of a spherical bearing.
4. The closed compressor of claim 2, wherein the auxiliary bearing
is configured of a spherical bearing.
5. The closed compressor of claim 1, wherein the electric element
is driven at a plurality of operation frequencies using an
inverter.
6. The closed compressor of claim 2, wherein the electric element
is driven at a plurality of operation frequencies using an
inverter.
7. The closed compressor of claim 3, wherein the electric element
is driven at a plurality of operation frequencies using an
inverter.
8. The closed compressor of claim 4, wherein the electric element
is driven at a plurality of operation frequencies using an
inverter.
9. A refrigeration device comprising: the closed compressor of
claim 1; and a refrigerant circuit that connects a radiator, a
decompressor, and a heat sink with piping in a ring shape.
Description
TECHNICAL FIELD
[0001] The present invention relates to a closed compressor using
an outer rotor motor as an electric motor, and a refrigeration
device equipped with the closed compressor.
BACKGROUND ART
[0002] In the related art, a type of closed compressor includes a
closed compressor in which a rotor is fixed to a crankshaft on an
upper side of a stator, an auxiliary bearing that pivotally
supports the crankshaft is provided below an electric motor, and
the stator is fixed to the auxiliary bearing (for example, see PTL
1).
[0003] The closed compressor of the related art disclosed in PTL 1
is described.
[0004] FIG. 3 illustrates a longitudinal-sectional view of the
closed compressor of the related art disclosed in PTL 1.
[0005] In FIG. 3, the closed compressor includes compressing
mechanism 2 that is accommodated in an upper portion of closed
vessel 1 and compresses refrigerant gas, and electric motor 3
provided below the compressing mechanism 2, in which compressing
mechanism 2 has crankshaft 4 that transmits rotation of electric
motor 3 to compressing mechanism 2.
[0006] Crankshaft 4 described above has an upper portion that is
pivotally supported by main bearing 6 provided in main frame 5 of
compressing mechanism 2, and a lower portion that is pivotally
supported by auxiliary bearing 7 fixed to a lower portion of closed
vessel 1.
[0007] Compressing mechanism 2 configures a scroll-type compressing
mechanism and is fixed to closed vessel 1 with fixed scroll 8
press-fitted into closed vessel 1.
[0008] Electric motor 3 is an outer-rotor type motor and is
configured to include stator 9 and rotor 10 provided to have a
predetermined clearance from outer circumferential surface 9a of
stator 9.
[0009] Stator 9 is fixed to closed vessel 1 by being fastened, with
bolt 11, to auxiliary bearing 7 fixed to closed vessel 1.
[0010] In addition, rotor 10 is fixed to crankshaft 4 via
bowl-shaped rotor housing 10a on an upper portion of stator 9.
CITATION LIST
Patent Literature
[0011] PTL 1: Japanese Patent Unexamined Publication No.
2006-170005
SUMMARY OF THE INVENTION
[0012] In such a configuration of the related art described above,
in order to assemble main bearing 6 and auxiliary bearing 7 with
accurate coaxiality and to prevent crankshaft 4 from twisting, it
is necessary to secure high accuracy in the coaxiality between
inner circumference 1a of closed vessel 1, outer circumference 8a
of fixed scroll 8, outer circumference 7a and inner circumference
7b of fixed portion 9b of auxiliary bearing 7 that fixes stator 9,
and inner circumference 10b of rotor 10 and inner circumference 10c
of rotor housing 10a. Moreover, it is necessary to manufacture the
component members with accuracy, and it is also necessary to
assemble fixed scroll 8 and main bearing 6 with accuracy.
[0013] In addition, since the clearance between inner circumference
10b of rotor 10 and outer circumference 9a of stator 9 is
determined by the assembly described above, the component members
need to be manufactured with high accuracy as described above in
order to form the even clearance.
[0014] In order to achieve high accuracy of the component members,
it is necessary to perform processes with high accuracy, and thus
costs of the processes increase.
[0015] On the other hand, the coaxiality between main bearing 6 and
auxiliary bearing 7 is degraded with low accuracy, thus, crankshaft
4 twists, and uneven clearances are formed between inner
circumference 10b of rotor 10 and outer circumference 9a of stator
9. In order to avoid contact of inner circumference 10b of rotor 10
with outer circumference 9a of stator 9, it is necessary to widen
the clearance, and thus, a problem arises in that efficiency of the
motor is reduced.
[0016] The invention provides a closed compressor that is able to
reduce an occurrence of twist of crankshaft without processing the
component members with high accuracy, and that is able to narrow
the clearance between the inner circumference of the rotor and the
outer circumference of the stator, thereby achieving high
efficiency and reliability at low costs.
[0017] The closed compressor in the invention has a configuration
in which a stator is fixed to a stator fixing member, the stator
fixing member is fixed to a member of a compression element, which
has a main bearing, and an auxiliary bearing is configured to be a
member separate from the stator fixing member and is fixed to a
stator fixing member.
[0018] In this manner, since it is possible to fix the stator
fixing member to the member of the compression element in a state
in which the even clearance is formed between the inner
circumference of the rotor and the outer circumference of the
stator, and it is possible to fix the auxiliary bearing to the
stator fixing member in a state in which the auxiliary bearing is
reliably coaxial to the main bearing, it is possible to narrow the
clearance between the inner circumference of the rotor and the
outer circumference of the stator, and it is possible to achieve
high efficiency of motor. Further, since it is possible for the
auxiliary bearing and the main bearing to be reliably coaxial to
each other even when the component members are processed with low
accuracy, it is possible to reduce costs in processing, to reduce a
loss in bearing, and to secure reliability thereof.
BRIEF DESCRIPTION OF DRAWINGS
[0019] FIG. 1 is a longitudinal-sectional view of a closed
compressor according to a first exemplary embodiment of the
invention.
[0020] FIG. 2 is a schematic diagram illustrating a configuration
of a refrigeration device according to a second exemplary
embodiment of the invention.
[0021] FIG. 3 is a longitudinal-sectional view of a closed
compressor of the related art.
DESCRIPTION OF EMBODIMENTS
[0022] Hereinafter, exemplary embodiments of the invention will be
described with reference to the accompanying figures. Note that the
invention is not limited to the exemplary embodiments.
First Exemplary Embodiment
[0023] FIG. 1 is a longitudinal-sectional view of a closed
compressor according to a first exemplary embodiment of the
invention.
[0024] In FIG. 1, a closed compressor according to the exemplary
embodiment has closed vessel 101 formed through drawing of an iron
plate, and electric element 102 and compressor body 104 having, as
a main body, compression element 103, which is driven by electric
element 102, are disposed inside the closed vessel. Compressor body
104 is elastically supported by suspension spring 105.
[0025] Further, refrigerant gas 106 such as hydrocarbon-based R600a
having a low global warming potential, for example, is sealed in
closed vessel 101 in a state in which the refrigerant gas has a
relatively low temperature at the same pressure as on a
low-pressure side of a refrigeration device (not illustrated), and
lubricant 107 for lubrication is sealed in a bottom portion in
closed vessel 101.
[0026] In addition, closed vessel 101 is provided with suction pipe
108 having one end that communicates with a space inside closed
vessel 101 and the other end that is connected to the refrigeration
device (not illustrated), and a discharge pipe (not illustrated)
that guides, to the refrigeration device (not illustrated),
refrigerant gas 106 compressed in compression element 103.
[0027] Compression element 103 is configured to include crankshaft
110, cylinder block 111, piston 112, conrod 113, or the like.
[0028] Crankshaft 110 has eccentric shaft 114, main shaft 115, and
auxiliary shaft 116 under main shaft 115.
[0029] Cylinder block 111 is integrally provided with cylinder bore
118 that forms compression chamber 117, and is also provided with
main bearing 119 that pivotally supports main shaft 115 such that
the main shaft freely rotates, and thrust ball bearing 121 that
supports a load of crankshaft 110 in a vertical direction on thrust
surface 120.
[0030] Piston 112 reciprocates in cylinder bore 118, and a piston
pin (not illustrated) is disposed to have an axial core that is
parallel to an axial core of eccentric shaft 114.
[0031] Conrod 113 has large end hole 124 and a small end hole (not
illustrated), eccentric shaft 114 is fitted into large end hole
124, and the piston pin is fitted into the small end hole. In this
manner, eccentric shaft 114 is connected to piston 112.
[0032] In addition, valve plate 126 provided with a suction hole
(not illustrated) and a discharge hole (not illustrated), a suction
valve (not illustrated) that opens and closes the suction hole (not
illustrated), and cylinder head 127 that blocks valve plate 126 are
fixed by being jointly fastened by a head bolt (not illustrated) in
an end plane of an opening of cylinder bore 118 on a side opposite
to crankshaft 110.
[0033] Cylinder head 127 is provided in a discharge space to which
refrigerant gas 106 is discharged, and the discharge space directly
communicates with a discharge pipe (not illustrated) via discharge
piping (not illustrated).
[0034] Electric element 102 is an outer-rotor type motor configured
to include rotor 128 fixed to the main shaft 115 side of crankshaft
110 via rotor housing 128b, and stator 129 disposed on an inner
side of rotor 128. Stator 129 is fixed to stator fixing member 130
with screw 131, and stator fixing member 130 is fixed to leg 132
extending downward from cylinder block 111. Auxiliary bearing 133,
which pivotally supports auxiliary shaft 116 of crankshaft 110 such
that the auxiliary shaft freely rotates, is fixed to stator fixing
member 130.
[0035] Hereinafter, operations and effects of the closed compressor
having such a configuration described above will be described.
[0036] The closed compressor configures a refrigeration cycle, with
suction pipe 108 and the discharge pipe (not illustrated) connected
to a refrigeration device (not illustrated) having a known
configuration.
[0037] In such a configuration, when electric element 102 is
energized, a current flows to stator 129, a magnetic field is
generated, and rotor 128 fixed to the main shaft 115 side of
crankshaft 110 rotates. Crankshaft 110 rotates in response to the
rotation thereof, and piston 112 reciprocates in cylinder bore 118
via conrod 113 that is attached to eccentric shaft 114 such that
the conrod freely rotates.
[0038] Suction, compression, and discharge of refrigerant gas 106
are performed in compression chamber 117 in response to the
reciprocation of piston 112.
[0039] In addition, since rotor 128 as a rotating member is
positioned above a lower end of stator 129, and is far from an oil
level of lubricant 107, it is possible to prevent lubricant 107
from being stirred such that it is possible to reduce a stirring
loss.
[0040] Next, an assembling method of electric element 102 to
compression element 103 will be described.
[0041] Rotor 128 is fixed through shrink-fitting to main shaft 115
side of crankshaft 110, and stator 129 is fixed to stator fixing
member 130 with screw 131.
[0042] Here, since an occurrence of distortion is reduced through
the assembling in the fixing performed with screw 131, compared to
press-fitting, shrink-fitting, or welding, it is possible to
improve the assembling accuracy. In addition, it is possible to
perform the assembling with simple equipment such that it is
possible to reduce manufacturing costs.
[0043] Stator 129 fixed to stator fixing member 130 in a manner
described above is installed in the inner side of rotor 128. After
positioning is performed with a jig such that an even clearance is
formed between inner circumference 128a of rotor 128 and outer
circumference 129a of stator 129, stator fixing member 130 is fixed
to leg 132 extending downward from cylinder block 111. In this
manner, it is possible to obtain coaxiality between inner
circumference 128a of rotor 128 and outer circumference 129a of
stator 129 with accuracy. Therefore, it is possible to narrow the
clearance between inner circumference 128a of rotor 128 and outer
circumference 129a of stator 129 such that it is possible to
achieve high efficiency of the motor.
[0044] Next, assembling method of auxiliary bearing 133 to stator
fixing member 130 will be described.
[0045] Auxiliary bearing 133 is temporarily joined to stator fixing
member 130, crankshaft 110 is rotated and the rotational torque is
measured while the position of auxiliary bearing 133 is changed.
When crankshaft 110 is twisted, the rotational torque increases.
Therefore, auxiliary bearing 133 is fixed to stator fixing member
130 at a position at which the minimum rotational torque is
produced. In this manner, since it is possible to perform the
assembling in a state in which crankshaft 110 has the minimum
twist, it is possible to reduce a sliding loss such that it is
possible to enhance reliability.
[0046] Further, when auxiliary bearing 133 is a spherical bearing,
it is possible to reduce an occurrence of the twist of crankshaft
110 without positioning auxiliary bearing 133 unlike the above
description such that it is possible to improve productivity.
[0047] In addition, in a case where the closed compressor of the
exemplary embodiment is caused to be driven using an inverter and
to rotate at a low speed, an effect of inertia of rotor 128
increases, compared to an inner-rotor motor in which rotor 128 is
disposed on the inner side, and thus it is possible to improve
efficiency in that torque variation is reduced and there is no need
to provide complicated control.
Second Exemplary Embodiment
[0048] FIG. 2 illustrates a refrigeration device according to a
second exemplary embodiment of the invention, and a configuration
in which the closed compressor described in the first exemplary
embodiment is equipped on a refrigerant circuit is adopted. Here, a
basic configuration of the refrigeration device is schematically
described.
[0049] In FIG. 2, refrigeration device 200 includes main body 201
configured to include a box member that has one open side and has
thermal insulation properties, and a door body which opens and
closes the opening, partition wall 204 that partitions the inside
of main body 201 into storage space 202 of goods and mechanical
chamber 203, and refrigerant circuit 205 that cools the inside of
storage space 202.
[0050] Refrigerant circuit 205 is configured of ring-shaped piping
connection with closed compressor 206, radiator 207, decompressor
208, and heat sink 209.
[0051] Closed compressor 206 is the closed compressor described in
the first exemplary embodiment.
[0052] In addition, heat sink 209 is disposed in storage space 202
provided with a blower (not illustrated). As illustrated with a
dashed-line arrow, cooling heat of heat sink 209 is stirred by the
blower so as to circulate inside storage space 202.
[0053] The refrigeration device described above is equipped with
closed compressor 206 described in the first exemplary embodiment.
In this manner, evenness of the clearance between the inner
circumference of the rotor and the outer circumference of the
stator and the coaxiality between the main bearing and the
auxiliary bearing are secured, and thereby efficiency of the motor
is improved, or an effect of reduction in the sliding loss is
achieved such that it is possible to operate the refrigerant
circuit with the closed compressor that has the improved
efficiency. Therefore, it is possible to reduce power consumption
of the refrigeration device such that it is possible to realize
energy conservation.
[0054] As described above, according to the invention, a closed
vessel accommodates the electric element and the compression
element that is driven by the electric element. In addition, the
compression element includes the crankshaft that is configured to
have the main shaft, the eccentric shaft, and the auxiliary shaft
provided under the main shaft, the cylinder block having the
cylinder bore provided to have a penetrating circular cylinder
shape, the piston that reciprocates in the cylinder bore, and the
conrod that connects the piston and the eccentric shaft. Further,
the compression element includes the main bearing that is formed in
the cylinder block and that pivotally supports a load in a radial
direction, which acts on the main shaft of the crankshaft, and the
auxiliary bearing that pivotally supports a load in a radial
direction, which acts on the auxiliary shaft of the crankshaft. The
electric element is the outer-rotor type motor that is configured
to have a rotor fixed to the crankshaft on the main shaft side and
a stator disposed on an inner side of the rotor, in which the
stator is fixed to the stator fixing member disposed on the
auxiliary shaft side, the stator fixing member is fixed to the
compression element, and the auxiliary bearing is fixed to the
stator fixing member.
[0055] In this manner, it is possible to fix the stator fixing
member to the compression element in a state in which the even
clearance is formed between the inner circumference of the rotor
and the outer circumference of the stator, with a jig or the like,
and further it is possible to fix the auxiliary bearing to the
stator fixing member in a state in which the auxiliary bearing is
reliably coaxial to the main bearing. Therefore, since it is
possible to secure evenness of the clearance between the inner
circumference of the rotor and the outer circumference of the
stator and the coaxiality between the main bearing and the
auxiliary bearing without using highly accurate component members,
it is possible to improve efficiency and reliability of the closed
compressor without an increase in costs.
[0056] In addition, according to the invention, the stator may be
configured to be fixed to the stator fixing member through
screwing.
[0057] In this manner, since it is possible to more improve the
assembling, compared to the case of fixing the stator through
press-fitting, shrink-fitting, or welding, it is possible to reduce
manufacturing costs of the closed compressor.
[0058] In addition, according to the invention, a spherical bearing
may be used as the auxiliary bearing.
[0059] In this manner, since the twist of the shaft is canceled
even in a case where the coaxiality between the main bearing and
the auxiliary bearing is rather degraded, it is possible to easily
perform the assembling such that it is possible to improve the
assembling of the closed compressor.
[0060] In addition, according to the invention, the electric
element may be configured to be driven at a plurality of operation
frequencies using the inverter.
[0061] In this manner, even in slow rotation with high torque
variation, the rotor is positioned on the outer side, thus a radius
of rotation increases, and an effect of the inertia increases.
Therefore, it is possible to improve efficiency in that torque
variation is reduced and there is no need to depend on control.
[0062] In addition, according to the invention, the refrigeration
device may include: the closed compressor described above; and the
refrigerant circuit that connects the radiator, the decompressor,
and the heat sink with piping in the ring shape.
[0063] In this manner, it is possible to reduce power consumption
of the refrigeration device through the installation of the closed
compressor having the improved efficiency such that it is possible
to realize energy conservation, and it is possible to improve the
reliability of the closed compressor. Therefore, it is possible to
improve reliability of the refrigeration device.
INDUSTRIAL APPLICABILITY
[0064] As described above, since it is possible to improve
efficiency of the closed compressor and the refrigeration device
according to the invention, the invention is not limited to an
electric refrigerator or an air conditioner for a household use,
and can be widely applied to a refrigeration device in an
industrial showcase, a vending machine, or the like.
REFERENCE MARKS IN THE DRAWINGS
[0065] 101 closed vessel [0066] 102 electric element [0067] 103
compression element [0068] 110 crankshaft [0069] 111 cylinder block
[0070] 112 piston [0071] 113 conrod [0072] 114 eccentric shaft
[0073] 115 main shaft [0074] 116 auxiliary shaft [0075] 118
cylinder bore [0076] 119 main bearing [0077] 128 rotor [0078] 129
stator [0079] 130 stator fixing member [0080] 131 screw [0081] 133
auxiliary bearing [0082] 200 refrigeration device [0083] 205
refrigerant circuit [0084] 206 closed compressor [0085] 207
radiator [0086] 208 decompressor [0087] 209 heat sink
* * * * *